endocrine Flashcards
what is the role of ADH
acts on CD to reabsorb water from urine
pathophys of diabetes insipidus
no ADH so kidneys cant concentrate urine as cant reabsorb water from the urine
causes polyuria and polydispsia because blood is so concentrated
what is primary polydipsia
drinking XS water causing polyuria and polydipsia
types of diabetes insipidus
nephrogenic
cranial
causes of nephrogenic DI
lithium
AVPR2 gene on Xchr
intrinsic kidney disease
electrolytes -> hypoK, hyperCa
causes of cranial DI
hypothalamus doesnt produce ADH for posterior pituitary to secrete
idiopathic
iatrogenic
tumour
meningits
TB
symptoms of DI
polyuria
polydipsia
dehydration
postural hypotension
hyperNat
IX and results of these in diabetes insip
UE-> hypernat
urine osmol = low
high serum osmol
water deprivation test
explain water deprivation test
no fluids for 8 hours
measure urine osmol
then desmopressin given
8 hours later then
measure urine osmol again
water dep test for cranial DI
after dep = low urine
after desmopressin = high urine osmol
as kidneys can still respond to ADH so can then dilute urine once desmopressin is given
nephrogenic DI water dep test results
after 8 hours water dep = low
after desmo = low
primary polydipsia water deprivation results
high after deprivation so dont need to give desmopressin as DI is already ruled out by this result
BP target for diabetic pt
<140/90 clinic
<135/85 AMBP
what is max dose of metformin
1g BD
prolactinoma vs somatroph pituitary adenoma
both may cause compressive symptoms such as headache or visual changes.
prolactinoma
- fertility and period problems
pituitary adenoma
- acromegaly symptoms
such as enlarged nose/forehead or hyperhydrosis, deepening of voice
appropriate dose of oral glucose if hypoG patient is able to eat/swallow
10-20g of glucose in the snack/gel
causes of raised prolactin
Causes of raised prolactin - the p’s
pregnancy
prolactinoma
physiological
polycystic ovarian syndrome
primary hypothyroidism
phenothiazines, metocloPramide, domPeridone
first line insulin regimen in kids?
multiple daily injection basal-bolus insulin regimen
diagnostic investogation results for DM
fasting > 7.0
random > 11.1
if asymptomatic need two readings
tx of myxoedemic coma
thyroxine and hydrocortisone IV
addisonian crisis vs myxoedemic coma
both will have low BP
myx will have significant weight gain (fluid overload) and dry skin
1st line IX for phaechromocytoma
urinary metanepherines
has replaced catecholamines
LH/FSH and testosterone in kallmans and klinefelters
kALLmans (ALL low)
- low LH/FSH, low testosterone
Klinefelters
- high LH/FSH with low testosterone
ramadan changes to meformin regime?
normal dose:
one-third = before sunrise
two-thirds = after sunset
monitoring blood test for carbimazole
FBC for agranulocytosis
reasons for falsely low HBA1c readings
G6PD def
sickle cell
hereditary spherocytosis
all reduce the lifespan of an RBC
reasons for falsely
high HBA1c readings
splenectomy
lifecycle of RBC is increased so there is more time for glycolysation of RBC
mx of phaeochromocytoma
surgery is definitive
before need to stabilise with alpha then beta blocker
eg phenoxybenzamine/phentolamine (non-selective) then propranolol
ABC
aplha beta cut
this is done as blocking alpha stops vasoconstriction so if we blocked beta first there would unopposed v.con = hypertensive crisis = cardiac arrest
what is the tx for high prolactin
cabergoline
neuropathic conditions caused by diabetes
gastroparesis - tx with metoclopramide
- will have erratic blood glucose levels
peripheral neuropathy - tx with duloxetine, amitryptyline etc
how to calculate serum osmolality
GUNN
glucose + urea + NA +NA
what is trousseaus sign
carpal spasm on inflation of BP cuff to pressure above systolic
due to hypocalcaemia
blood test results for pagets
high ALP
calcium is normal
ix for acromegaly
first do IGF1 -> if raised then do OGTT (high) and serial glucose measurements to confirm diagnosis
advise to give when taking levothyroxine
take calcium or iron supplements 4 hours after/ before
affects absorption
TSH low and T4 low?
secondary hypothyroidism
cause is central therefore need to do an MRI rather than anti-TPO
usually pituiary insufficiency
symptoms for kallmans syndrome
Tallman, Small-ballman, Can’t smell at allman!!!
when to treat subclinical hypothyroidism
if the TSH level is > 10 mU/L on 2 separate occasions 3 months apart
symptoms for men 1
Peptic ulceration, galactorrhoea, hypercalcaemia
Peptic ulceration, galactorrhoea, hypercalcaemia points to a diagnosis of?
MEN 1
